Finding the Third Proportional to 300,712.50 and 648,434.25

Step by Step Solution

1. Step 1: Write the proportion equation
   300,712.50 : 648,434.25 = 648,434.25 : x
2. Step 2: Convert to fraction form
   300,712.50/648,434.25 = 648,434.25/x
3. Step 3: Cross multiply
   300,712.50x = 648,434.25 × 648,434.25
4. Step 4: Simplify right side
   300,712.50x = 420,466,976,573.06
5. Step 5: Solve for x
   x = 420,466,976,573.06/300,712.50
6. Step 6: Final answer
   x = 1,398,235.78